The object of the present invention is to provide a microsphere which has a slow-release period of from about two weeks to about four weeks following administration, enables a higher content of a drug to be included, suppresses an initial burst of the drug, and enables the drug to be maintained at an optimal, effective blood concentration during the slow-release period.
In a microsphere containing a drug and PLGA, the above problems can be resolved by setting: (1) the amount of lactic acid/glycolic acid copolymer per part by weight of the drug to from about 3 to about 10 parts by weight; (2) the microsphere to an average particle size of from about 20 to about 50 µm; and (3) the lactic acid/glycolic acid copolymer to a weight-average molecular weight of from about 10,000 to about 50,000 and to a lactic acid/glycolic acid compositional ratio of from about 75/25 to about 50/50.
In addition, the microsphere, by promoting the production of various endogenous repair factors, is useful against various tissue disorders.
本发明的目的是提供一种微球,该微球在给药后具有约两周到四周的缓释期,能够包含较高含量的药物,抑制药物的初始迸发,并使药物在缓释期保持在最佳的有效血药浓度。
在含有药物和 PLGA 的微球中,可以通过设置以下条件来解决上述问题:(1) 每份药物重量的
乳酸/
乙醇酸共聚物的量为约 3 至约 10 份重量;(2) 微球的平均粒径为约 20 至约 50 微米;(3)
乳酸/
乙醇酸共聚物的重量平均分子量为约 10,000 至约 50,000 和
乳酸/
乙醇酸的组成比例为约 75/25 至约 50/50。
此外,微球通过促进各种内源性修复因子的产生,可用于防治各种组织疾病。